The present invention relates to a new and improved integral hydraulic power unit to be used in connection with elevator constructions.
A conventional type of elevator utilizes a hydraulic system having one or more hydraulic rams which raises and lowers the elevator car. The rams are extended by pumping hydraulic fluid into the ram cylinders, while lowering the car is performed by allowing fluid to vent from the cylinders, typically solely due to the compressive load on the ram by the weight of the elevator car. Conventional technology locates the reservoir for the hydraulic fluid, as well as a pump and pump motor, in a machine room adjacent the elevator hoistway. Use of a separate machine room requires additional building space beyond that for the elevator hoistway, and requires associated connections between the apparatus located therein and the hydraulic cylinders located in the hoistway. While locating the hydraulic equipment in a separate machine room provides a degree of design flexibility, it adds to the overall cost of the construction, and utilizes expensive space which often can be put to more productive use.
It is accordingly a purpose of the present invention to provide a hydraulic power unit that is integrated with the elevator lift and is located within the elevator hoistway.
A further purpose of the present invention is to provide a hydraulic power unit having a reservoir which may be sized and located to support the hydraulic jacks for a twin-jack hydraulic installation.
Still a further purpose of the present invention is to provide an integral hydraulic power unit which may be installed in a hoistway pit, and which can accommodate a variety of pit conditions.
In accordance with the foregoing and other objects and purposes, an integral elevator hydraulic power unit constructed in accordance with the present invention comprises a chassis which is adapted to be mounted and installed upon the floor of the elevator hoistway. The chassis supports the elevator lift ram means, and is constructed with an integral hydraulic fluid drip pan to serve as a sump for hydraulic fluid which may leak from the ram means. A hydraulic drive, including both a fluid reservoir and a pump/motor unit, are mounted to the chassis and are operatively connected to the ram means to control the passage of hydraulic fluid to and from the ram means to effect elevator travel.